The quality of life (QL) concept has led to extensive scientific research and has been increasingly used by health care professionals treating a wide range of diseases. This paper addresses the historical use of the concept and specific issues linked to conceptual and methodological aspects of the QL construct within the health care context. Reviewing the literature, two aspects stand out: subjectivity and multidimensionality. In the methodological field, the construction and/or adaptation of QL measurement instruments appear as a significant trend. Theoretical and methodological efforts have helped clarify and improve the concept's adequacy. The QL construct is definitely interdisciplinary, encompassing contributions by different areas of knowledge and research, thereby improving its conceptual and methodological potential as a research instrument. Therefore, use of the concept can actually help improve both the quality and the integrated, multidimensional nature of health care from a perspective that views the latter as a basic citizen's right.